Question
A model car of mass 8.0 kg slides down a frictionless ramp into a spring with spring constant k = 5.5 kN/m .
(a) The spring experiences a maximum compression of 20 cm. Determine the height of the initial release point.
(b) Calculate the speed of the model car when the spring has been compressed 12 cm.
(a) The spring experiences a maximum compression of 20 cm. Determine the height of the initial release point.
(b) Calculate the speed of the model car when the spring has been compressed 12 cm.
Answers
R_scott
m g h = 1/2 k x^2 ... h = k x^2 / (2 m g)
h = 5.5E3 N/m * (.20 m)^2 / (2 * 8.0 kg * 9.8 m/s^2) = ? m
h = 5.5E3 N/m * (.20 m)^2 / (2 * 8.0 kg * 9.8 m/s^2) = ? m
R_scott
forgot part (b)
m g h - (1/2 k x^2) = 1/2 m v^2 ... v^2 = [m g h - (1/2 k x^2)] * 2 / m
v^2 = [(8.0 * 9.8 * h) - (1/2 * 5.5E3 * .12^2)] * 2 / 8.0 = ? (m/s)^2
m g h - (1/2 k x^2) = 1/2 m v^2 ... v^2 = [m g h - (1/2 k x^2)] * 2 / m
v^2 = [(8.0 * 9.8 * h) - (1/2 * 5.5E3 * .12^2)] * 2 / 8.0 = ? (m/s)^2